Design of a high resolution positron emission tomograph using solid state scintillation detectors

Abstract

A novel type of positron camera achieving nearly isotropic spatial resolution and uniform sensitivity throughout the useful field of view is proposed. The design is based on a quad scintillator dual-channel detector module using two avalanche photodiodes as photodetectors. Original features include bilayered scintillators to measure the depth of interaction, tilted detectors relative to the radial direction to ensure proper sampling in a stationary mode, multiring capability, and an independent acquisition channel for every discrete detector. Significantly better resolution is obtained toward the edges of the camera field, and the sampling uniformity near the center is improved. Multiring systems with a slice thickness of 5 mm can be implemented to achieve true volume imaging with symmetrical 3-D spatial resolution. The performance of the proposed design is analyzed in terms of resolution, sensitivity, contrast, and field uniformity.